The present invention generally relates to electronic equipment, and more specifically to a card guide for receiving one or more circuit cards within an electronic device.
The reliability and performance of an electronic device such as a piece of avionic equipment or the like are closely related to the temperature at which the device's internal electrical and electronic components must operate. For example, electronic devices may include a number of integrated circuit components mounted on one or more circuit cards supported within the device's chassis or housing. During use, these components may generate excess heat which must be dissipated to prevent damage to the components or degradation of their performance.
Typically, heat generated within an electronic device is dissipated via convection by passing a coolant, usually air, across the faces of the circuit cards contained therein. A card guide receives the circuit cards and holds them parallel to the flow of the coolant. Preferably, the card guide allows the circuit cards to be easily inserted in and removed from the electronic device during maintenance.
It is often desirable to regulate the amount of coolant provided to the electrical and electronic components within the electronic device. This has traditionally been accomplished by placing a flow metering plate within the chassis of the electronic device to restrict the flow of coolant over the circuit cards. However, the flow metering plate increases the weight of the electronic device and occupies valuable space inside its chassis. This is particularly undesirable for avionic equipment wherein the size and weight of the equipment may adversely affect the performance of the aircraft.
Consequently, it would be advantageous to provide a card guide having a means for regulating the flow of a coolant, such as air, across the circuit cards of an electronic device thereby eliminating the need for a flow metering plate while retaining its function.